Sciencemadness Discussion Board

Ebonex Electrode

dann2 - 25-2-2008 at 16:31

Hello,

Another new anode thread.

Anyone know much about Ebonex.
I found the enclosed document on Google books.
This stuff would not be impossible for the back yard tinkerer to make. A oven with H2 (from water + electricity) and some Ti. It appeart to make a suitable Substrate for other layers. Lead Dioxide comes to mind.

There is also a US Patent on the same thing, 'Making TiO2 conductive'.
US 2957787
Dann2

Attachment: Towards an conductive ceramic.pdf (601kB)
This file has been downloaded 2072 times


jpsmith123 - 26-2-2008 at 05:40

Hello Dann2,

Coming up with a better substrate would definately solve a lot of problems. Apparently no intermediate layer would be needed and there'd be no passivation...with lifetime defined strictly by wear of the outer catalytic layer. Once your efficiency drops to an unacceptable level you just recoat the substrate I would think.

Anyway, I wonder if a film of this stuff could be made electrolytically somehow? If so this may explain one weird thing I saw when I was fooling around with Ti. One day I decided to see what would happen if hydrided Ti was anodically polarized in brine. It passivated after a short time...all except for one small patch of area, that is. One small area just kept making bubbles until I stopped the experiment after an hour or two. Many of those pieces of Ti I was using were not etched in Oxalic acid...I was in a hurry so I merely sanded them and rinsed them in detergent solution. I wonder if a small spot of TiO2 may have been left on that piece and somehow converted to Ti4O7 when I hydrided it?

Rosco Bodine - 26-2-2008 at 10:19

Ebonex was tested as a substrate for a perchlorate anode , IIRC it was given an electrodeposited PbO2 working coating , and for some reason it did not perform satisfactorily and was not pursued . I can't remember
the journal citation now , but it was something brought up
before in one of the other threads along with the journal reference . I don't remember the details except that I know that ebonex came up before as seeming like a good idea that didn't prove out for whatever reasons .

dann2 - 26-2-2008 at 12:00

Hello,


Atricle in reference section 18-2-2008:

http://www.sciencemadness.org/talk/viewthread.php?tid=9319&a...

The electrochemistry of Magn li phase titanium oxide
ceramic electrodes Part II: Ozone generation at Ebonex and Ebonex[lead
dioxide anodes
J. E. GRAVES, D. PLETCHER, R. L. CLARKE, F. C. WALSH
Journal of Applied Electrochemistryv 22, n 3, Mar. 1992, pp 200-203

It seems to be OK for Ozone. I would imagine it is OK for Perchlorate (when coated with LD or whatever).

Would rather make Ebonex with H2 as opposed to H2S. Would rather go out with a big bang that a big stink if it all went wrong :P

Dann2

Rosco Bodine - 26-2-2008 at 12:41

That seems very similar to the reference I remembered
reading about the tests of ebonex substrate/PbO2 anodes , that the combination worked and made perchlorate , but for some reason the cell efficiency was anomalously low . It seems to be the same story for the ozone .
And I can't explain that result in either case as it would seem that the substrate should be irrelevant with respect to the working coating , if all the substrate is doing is acting as a conductor . I didn't understand what the difference should be for PbO2 applied on top of whatever substrate so long as the current from the substrate was
being efficiently conducted to the PbO2 .......and frankly
I still don't understand the reported anomalous drop in efficiency which appears when ebonex is the substrate . Go figure .

[Edited on 26-2-2008 by Rosco Bodine]

dann2 - 26-2-2008 at 13:11

Hello,

Unless they are mixing up Power Efficiency with Current Efficiency (ie. voltage rise) but thats unlikely.

Dann2

Rosco Bodine - 26-2-2008 at 14:57

This is one of those things that maybe nobody understands .....maybe there is an unidentified EM or electrostatic field that is associated with the electrode
coatings as a local phenomena and maybe the same
thing is what makes some catalysts work ....I sure don't know what accounts for this scenario , but evidently it
is so . I have seen a similar thing reported for other
combinations of substrates , like for working coatings
deposited onto platinum , or a different substrate , then behaving differently based on the material which is underneath , when the working coating is precisely the same . It's a damn mystery.... I tell you :D

If anybody has any explanation , by all means ....teach:D

[Edited on 26-2-2008 by Rosco Bodine]

chloric1 - 26-2-2008 at 15:03

I realize that Ebonex is supposed to be hardy and durable but we are talking lower oxides of titanium. Maybe under certain conditions, the lead dioxide interface with the Ebonex is compromised by a redox reaction.

I am glad this thread is about black anodes and not an alternative black language:D:P Kinda freaked first time I seen the Ebonex posting.

Rosco Bodine - 26-2-2008 at 15:15

Soooooooo with regards to the anomalous efficiency drop
for PbO2 working coatings applied to an Ebonex substrate,
all we can say is " Sup Dood " ??? :P:D
" Wudzapenin' " ??? :D:D
" I axed yoo uhkestyun " :D:D;)

[Edited on 26-2-2008 by Rosco Bodine]

Swede - 16-12-2009 at 10:40

This is an ancient, necropostic thread, but it is the only eboxex hit on SMDB. I have been in contact with Atraverda in the UK in an attempt to obtain some samples. To me it appears to have possibilities, and I'd love to find a bit. If they come through, I'll post some pics and perhaps have a go with it.

Rosco Bodine - 16-12-2009 at 12:59

Just yesterday i was looking at this link
http://www.springerlink.com/content/x300wwwhg0t6306u

There's possibly a book on Ebonex on gigapedia
Development of a New Material - Monolithic Ti4O7 Ebonex Ceramic
http://gigapedia.info/1/Development%20of%20a%20New%20Materia...

Swede - 22-12-2009 at 08:00

Those Hosers in the UK didn't even bother answering my email. :mad:

I'm not looking for FREE Ebonex. I'd pay, but sometimes these big corporations simply do not even bother with a little guy. It's odd, I've either had great responses from big companies, or no response. And I always treasure those that do business with individuals. Usually, the corps have samples of material that they'd provide to NASA or a University on request, and there shouldn't be a reason (other than greed) that they cannot sell such sample material to small-scale investigators.

ChrisWhewell - 22-12-2009 at 09:01

Some of Eltech's patents covering their DSA(TM) electrodes are probably expired. That's some rugged stuff that can be prepared in a benchtop muffle furnace.